Sizing tank with electro-mechanical controlled water flows

ABSTRACT

A vacuum sizing tank configured to provide controlled fluid flow. A fluid control system and a vacuum sizing tank utilizing electronic controls to create and maintain controllable fluid flow within the tank. Flow meters may measure the flow in and out of the tank to maintain consistency. Temperature meters may measure the temperatures for each of the flows to maintain consistency. An electronic circuit may compare the values with preset values. Any difference between the values may trigger change by varying the voltage applied to a variable speed water pump.

PRIORITY CLAIM

This application is a continuation-in-part application which claims thebenefit of U.S. Non-provisional application Ser. No. 13/410,847 filed onMar. 2, 2012, which claims priority to Provisional Application No.61/448,387 filed Mar. 2, 2011.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present disclosure relates generally to extrusion, and in particularrelates to extrusion processing. More particularly, the presentinvention relates to a system capable of applying and controlling waterand vacuum applied to extrudate material.

2. Description of the Prior Art

A typical method for forming parts from plastic utilizes the extrusionmethod. This method involves a plurality of materials and compoundswhich are extruded from an extruder. Upon immediately exiting theextruder, the plastic may remain in the molten state. In this state, themolten plastic is easily susceptible to deformation up until it issufficiently cooled to a solid state.

Accordingly, the molten extrudate must be subject to a strictlycontrolled atmosphere until it solidifies. There are several methodsutilized to minimize the unwanted deformation of the molten extrudate.

While all of these methods minimize unwanted deformations in the moltenextrudate, controlling the water itself is an important factor. Waterhas a mass significant with respect to small extrudate. Any unwantedcurrents, temperatures, or flows, will have unwanted forces acting onthe extrudate. An unwanted flow can push on the wall of thin tubeextrudate, resulting in deformation of the desirable circular shape.Flows can also push and pull on the extrudate as the result of forces(eddies). Varying temperatures can change the way extrudate cools,introducing deformations. To further complicate things, rollers may beintroduced to prevent hollow extrudate from floating upwards.

Previously, efforts found to control the water flow were minimal.Efforts found included manual attempts to maintain uniform flow. Thisincluded simple mechanical valves which were adjusted by an operator.Typically, the valves are completely opened, allowing flow into thetank. This process leaves much to be desired, the control is far fromprecise, no consideration is given to flow rates or uniformity along thelength of the extrudate. Further the process does little to obviate theabove mentioned problems present in the prior art.

SUMMARY OF THE INVENTION

The subject matter of this application may involve, in some cases,interrelated products, alternative solutions to a particular problem,and/or a plurality of different uses of a single system or article.

It is an object of the present invention to provide a system capable ofmaintaining the combination of vacuum and water applied in the extrusionprocess. It is another object of the invention to create a systemcapable of controlling the vacuum and water in a specific fashion.

The present invention utilizes a vacuum sizing tank substantially closedto the atmosphere. The vacuum sizing tank may comprise an enclosedtrough capable of holding water, holding a plurality of vacuum and aplurality of different water flows. The vacuum sizing tank alsocomprises an opening for the ingress of molten plastic extrudate and asecond opening for the egress of cooled plastic extrudate.

In one aspect of the present invention, the vacuum tank can be modifiedby outfitting it with a water pump and various manifolds. The water pumpapplies pressure to the various manifolds, which direct the water intoand through the tank in a controlled fashion. One or a plurality ofvalves may be further utilized to direct and control flow from the pumpto inlet or inlets of the tank. The water may be maintained at aspecific level using an adjustable drain. The vacuum is applied in acontrolled manner, which may or may not be in relation to the waterflows.

In yet another aspect of the present invention, the vacuum tank isequipped with a water pump to supply water to the vacuum tank. Thevacuum tank may also be equipped with a second water pump to pull waterout of the tank. Both pumps may allow for additional control of theresulting water flow through the vacuum tank.

In another aspect the vacuum tank utilizes various water pumps andvacuum systems to create a plurality of water flows and vacuum flowswithin the tank. The water and vacuum systems are further enhanced bythe addition of various sensors which directly measure and monitor flowsthroughout the system. The sensors may then be connected to variouscontrollers to measure, control, and manipulate the system.

In yet another aspect the vacuum tank utilizes various water pumps andvacuum systems to create a plurality of water flows and vacuumpressures. The vacuum tank has additional physical features such astooling which may assist in directing the water flow in a more desirablefashion.

In another aspect the invention may be equipped with various water pumpsand vacuum systems to create a plurality of water flows and vacuumpressures. Each water flow may have a different temperature. The vacuumtank has additional physical features which may assist in directing thewater flow in a more desirable fashion. Furthermore, these physicalfeatures may be modular and/or removable to allow a variety ofcombinations to provide enhancement for the flows.

In yet another aspect the vacuum tank may be outfitted with variouswater pumps and vacuum systems to create a plurality of water flows andvacuum pressures. The vacuum tanks may utilize various sensors andfeatures to aide in water flow. Furthermore, the vacuum tank my beequipped with a controller to increase water flow, if measured flow hasfallen below a predetermined value. The controller may also decreasewater flow, if measured flow has risen above a predetermined value.Additionally, vacuum pressure may be controlled in a similar fashion.Vacuum pressure may be fluctuated relative to various systems, such aswater flow or with various predetermined values.

In another aspect the vacuum tank may be outfitted with various waterreservoirs at varying heights relative to the vacuum tank. Thereservoirs may utilize various sensors, geometries, and features to aidein the controlled flow throughout the vacuum tank. Furthermore, thesephysical features may be modular, adjustable, and/or removable to allowa variety of combinations to provide enhancement for the flows.

In yet another aspect the present invention may be outfitted with vacuumand water pumps and may comprise several tanks such that pressure, waterflow and temperature is controlled in incremental sections. Theseincremental sections may be referred to as ‘zones’ and may utilize avariety of controls including but not limited to vacuum control, waterflow control, temperature control, and furthermore may include sensorsto monitor all attributes and may include a control system to utilizethe data for precise manipulation.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described by way ofexample only, with reference to the attached figures wherein:

FIG. 1: Perspective external view of an embodiment of the sizing tank isprovided.

FIG. 2: Closer perspective external view of an embodiment of the sizingtank is provided.

FIG. 3: Detail perspective view of an embodiment of the sizing tank isprovided.

FIG. 4: Simple diagram consisting of components in FIG. 1 is provided.

FIG. 5: A perspective cutaway view of an embodiment of the sizing tankis provided.

FIG. 6: A rear perspective cutaway view of an embodiment of the sizingtank is provided.

FIG. 7: A partially exploded rear perspective cutaway view of anembodiment of the sizing tank is provided.

FIG. 8: A detail view of one embodiment of the trough of the sizing tankis provided.

FIG. 9: A perspective view of one embodiment of the trough of the sizingtank is provided.

DETAILED DESCRIPTION

The process of extrusion contemplated in the present invention involvesthe use of a vacuum tank. The vacuum tank is placed inline with theother pieces of machinery used in the extrusion process. As theextrudate exits the extruder, the extrudate is in molten form. Theextrudate needs to be properly cooled, such that it may be able toachieve desirable dimensions and tolerances.

Vacuum sizing tanks typically include a tank which holds fluid such aswater and vacuum is applied. Molten plastic extrudate enters one end ofthe tank, and the cooled plastic part exits through the other end.Vacuum applies negative pressure to the tank and water applies a mediumwhich removes heat from the part. The tank remains substantially closedto the atmosphere, with the only significant openings to atmospherebeing the entrance and exit of the plastic part. It should be understoodthat this process may involve liquids other than water such as oils,organic solvents, or water-based solution, among others, withoutstraying from the scope of the present invention. However, in someembodiments, it is possible to use the present invention withoutapplying a vacuum, and with the tank being open to the atmosphere.

The resulting forces of vacuum and water, sometimes benefited inparallel with tooling sets, allow the molten extrudate to maintain adesired shape. This is the traditional practice utilized and unchangedfor nearly 25 years.

Today, current innovation has allowed for extrusion profiles to shrinkdramatically. The resulting reduction in overall shape and mass, hasallowed the profiles to be more sensitive and susceptible todeformation. The profiles need to be handled with precision and allvariables surrounding the extrudate need to be minimized. The presentinvention allows for precision extrusion making very small profilespossible. These extruded products may be particularly useful in numerousindustries where small diameter and thin wall tubing are valued. Inparticular, the medical and medical device industry may benefit fromplastic extrusions made possible by the present invention.

Additionally, current innovation has introduced thousands of newpolymers. The new polymers may be sensitive to varying temperatures asthey are cooled. Varying cross sectional areas also demand varyingtemperatures to allow for proper (even) cooling to minimize deformation.The profiles need to be introduced into a controllable atmosphere whichmay include certain temperature profiles along the vacuum tank system.

The invention described herein can allow the random and unpredictableforces generated by water and vacuum, and their resulting flows, withinthe vacuum tank to be minimized and manipulated in a desired fashion.Control of these various flows of vacuum and water allows for vastlyenhanced precision in the extrusion process. In one example, testingproved that, on a tube 0.135 inch (″) outer diameter (OD, with 0.005″wall thickness, the tolerances on the inner diameter (ID)/OD was just+/−0.0007″. Alternatively, this same test on a competing device yieldedtolerances on the ID/OD of approximately +/−0.002″. As such the presentinvention proves vastly superior to the existing art in precisionextrusion.

The tank is to have a trough capable of holding a body of water deepenough for the plastic part to submerge, and travel in. The body ofwater is to have water flow which is controllable such that a uniformflow is achieved. Water may enter the trough through one or a pluralityof water inlets. The inlets may be positioned at various points alongthe trough such as the sides, the front or the back. In one embodiment,the tank may have two water inlets, a first inlet on the left side and asecond inlet on the right side. Water may exit the device through one ora plurality of water outlets. The outlets may be positioned at variouspoints along the trough such as the sides, the front or the back.

In one embodiment, this uniform flow may be achieved by variable speedwater pumps. Furthermore, water pumps may control and manipulate waterflow in and out of the tank. A bleeder valve may be added incommunication with tank to aide in control of water level or simplyrelease water when desired. The bleeder valve may also be introduced toany flow entering or exiting the tank.

The trough may further have one or a plurality of baffles positionedalong its length. The baffles may serve to increase flow consistency,and to stabilize water inlet and/or outlet.

The trough may additionally have one or a plurality of flow channels.The flow channels may control and direct the inlet water flow andcontrol and direct the outlet water flow, and which may serve toseparate the water flow in the trough into separate zones.

The trough may further have ridges and channels machined into it. Theridges and channels may serve to increase flow consistency, and tostabilize water inlet and/or outlet.

A splitter may be positioned at an outlet end of the trough. Thesplitter may be substantially ‘V’ shaped, with the narrow end facing theflow. The splitter may serve to direct flow away from the center of thetrough. At an end of the broader portion of the splitter is an outletallowing the fluid flow to be directed by the splitter towards theoutlet on either end of the splitter. In one embodiment the outlet maybe a slit shape extending from nearly the top of the tank to the bottomto provide smooth, laminar flow out of the device without causing anydead zones of stagnant or turbulent water.

Water flow may be controlled in a variety of manners. For example, byutilizing an electrical feedback control system to control water flowwithin a vacuum sizing tank will result in a more uniform water flow.The flow of water and vacuum will be controlled and manipulated in aplurality of combinations, which may include temperature. Controllingthese flows may reduce unwanted forces applied to the extrudate. As aresult, the final product which involves passage of molten plasticthrough the vacuum sizing tank will be improved and allow for furtherinnovation with the extrusion process.

In one embodiment, the water flow is controlled through the trough to bea laminar flow.

In another embodiment, the water flow is controlled through the troughto be substantially laminar, wherein the flow involves only minimaleddies.

In yet another embodiment, the water flow is substantially uniformacross the entire length of the trough, such that from the ingress ofthe extrudate to the egress of the extrudate, the water flow is at anearly constant rate and has a nearly constant flow profile.

Vacuum is to be applied to the small volume of air above the body ofwater. In one embodiment, vacuum may be applied and controlled in amanner separate from the control and manipulation of water flows. Inanother embodiment, vacuum can also be applied and controlled in amanner coordinated with the control and manipulation of water flows. Avacuum control system may include a pressure sensor positioned withinthe tank, a controller and a vacuum system. The amount of vacuumsupplied may be adjusted based on pressure measured within the tank andinterpreted by the controller. Vacuum is to be applied and controlled ata predetermined value set with electronic or mechanical control. Vacuumcan be applied as a plurality of values and maintained such thatconstant negative pressure can be applied in coordination with waterflow. The vacuum may be applied at a vacuum outlet, which may bepositioned anywhere on the sizing tank. In one embodiment, the vacuumoutlet is positioned above the trough so water does not enter the vacuumoutlet.

Vacuum may be any type of vacuum system capable of drawing a vacuum onthe interior of the tank. In one embodiment a vacuum pump may be used.In another embodiment, a blower may be used.

In still another embodiment, a vacuum ejector may be used. The vacuumejector may be connected to a shop air connection or other pressurizedgas flow system. The ejector may use the pressurized air to draw avacuum on the interior of the tank. An electronic regulator may be incommunication with the pressurized air flow to the ejector to provideprecision control and maintenance of the air flow and in turn the vacuumapplied to the tank by the ejector. A pressure sensor positioned withinthe tank and/or along the vacuum line may communicate with theelectronic regulator to direct the regulator to adjust the vacuum draw.In one embodiment, the ejector may be a three stage diffuser vacuumejector. Testing indicates that the vacuum ejector may provide greaterprecision, control and maintenance than any other methods currentlyknown in the art.

In another embodiment, the vacuum control system works with a precisionelectronic pressure regulator. The pressure regulator controls an outputof a high pressure air source via a ten turn potentiometer to a veryprecise level. The potentiometer controlled air is then fed to vacuumejector using a three stage diffuser constructed to generate preciselycontrolled vacuum, eliminating all inefficiencies associated withmotors/blowers.

When water flows are measured to be uneven or changing in an undesirablefashion, a water flow detector may communicate to controller and adjustthe water pump speed accordingly. The water flow detector may bepositioned in any location of the trough capable of measuring waterflow. In one embodiment, a plurality of water flow detectors may beemployed. Flow may be introduced at one or a plurality of locations,such that uniform flow is achieved along the length of the tank. Waterpumps may control each inlet of flow via a manifold, or separately, witha pump dedicated to each inlet. Further, water flow may exit from thetrough at one or a plurality of locations. It should be understood thatthe present invention may be operated as a water bath without a vacuumas well as a vacuum tank with a vacuum drawn within it.

The control and monitoring of vacuum and/or water flow may be performedat numerous sections or zones of the trough by positioning detectors,controllers, water inlets or outlets or valves in specified zones. Sucha configuration may serve to provide enhanced water flow, allowing forvarying flow conditions, vacuum control and consistency across thezones.

In the instance of water flow being introduced and/or manipulated onindividual basis, each case will be a designated zone which may haveindividual characteristics and predetermined values. Thus, the operatorwill have the option and ability to manipulate the flow throughout thetank, for each particular product. The detector and controller resultsin a water flow throughout the vacuum sizing tank which is maintainedand manipulated as desired.

In one embodiment, the trough is sized to be large enough to createnumerous temperature zones along the length the trough. For example, toachieve ideal processing of tubing, the water may be at a firsttemperature in a first zone adjacent to the inlet of the moltenextrudate, a second temperature in a second zone at the middle portionof the trough, and a third temperature in a third zone at the exit pointof the extrudate.

In an alternate embodiment, the tank may be formed as a cylindricalpipe. The pipe may have an extrudate inlet and extrudate outlet atopposing sides. A fluid flow controller may be positioned at theextrudate inlet side. In one embodiment, the fluid flow controller maybe conical in shape. At a tip of the conical shaped flow controller maybe an aperture through which the extrudate may enter the tank. At a baseof the conical shaped flow controller may be a plurality of fluid inletports. In one embodiment, these fluid inlet ports may be spacedequidistantly about the circumference of the cone. By forming the tankas a cylinder, the flow profile is substantially more uniform about atubular extrudate than a rectangular shaped tank, as eddies and “deadzones” are minimized. Moreover, the conical flow controller andcylindrical shape may allow the flow to mimic the flow of thecylindrical extrudate. As such, minimal undesired forces are applied tothe wall of the extrudate, and heat transfer from the extrudate to thefluid is substantially more controllable. The present embodiment may beparticularly applicable to extruded tube shapes because the trough has asimilar shape (cylindrical) to the extruded tube allowing flow to flowalong the extrudate and with the extrudate to minimize forces againstit.

In one embodiment the conical flow controller may form a conicalinterior through which the extrudate may enter the tank.

In another embodiment, a vacuum tank may apply a vacuum to an air spacewithin the tank.

In still another embodiment, a second conical flow controller may bepositioned at an extrudate outlet end. In this embodiment, the waterflow inlet may be directed at the second conical flow controller suchthat the water flow is in an opposite direction from the extrudate flow.

In operation, molten extrudate may enter the tank through the tip of theflow controller. Fluid may enter through the plurality of inlets. Thesurface of the conical flow controller may serve to smoothly direct theinlet fluid flow along its surface flowing towards its end where itmeets the extrudate. In this embodiment, the flow may be controlled tominimize unwanted forces. In embodiments configured as described, flowwill be in the direction that the extrudate travels. Further, the flowcontroller may serve to create a smooth, controlled and substantiallylaminar flow profile. As such, the present invention may allow forenhanced precision of extrudate as well as allowing for very smallextruded products.

In another particular embodiment, the present invention may beconfigured as one or a plurality of inserts that may be placed in anexisting rectangular or other shaped vacuum sizing tank, allowingretrofitting of the rectangular tank into a tank of the presentinvention. This embodiment may be applied to any of the embodimentsshown in the figures below, and may be as simple as inserting the troughinsert into the existing rectangular trough, and connecting any openingsand/or ports as defined by the trough insert. The insert embodiment maybe formed of any material capable of being shaped, and retaining itsstructure when exposed to water and/or other fluid. Non-limitingexamples of materials of which the insert may be made include, but arenot limited to: metals, plastics, composites, wood, ceramics, and thelike. The insert may be formed in any manner either known in the art orto be developed in the future, these manners may include, but are notlimited to: injection molding, rotational molding or similar moldingprocesses, may be machined, stamped, 3D printed, and the like.

It should be understood that the vacuum sizing tank, trough, and relatedelements may be of varying size and shape without straying from thescope of the present invention.

FIGS. 1, 2 and 3 show a vacuum sizing system located generally at 10.The molten extrudate enters the system 10 at opening 13 through sizingtooling 14, located on trough 12. The extrudate first undergoes coolingin trough 12 which may hold water, air and vacuum. The extrudate leavesthe trough tank 12 at opening 15 and enters auxiliary cooling tank 11 atopening 15. Opening 15 may be considered a common area for extrudatepassage which is not significantly open to atmosphere. Lastly, theextrudate exits at outlet 17 where an airwipe (not shown) may beinstalled to assist in water removal.

It should be understood that the configuration shown in FIG. 3 may beoperated in both directions. In other words, in one embodiment, themolten extrudate may enter at 50. In another embodiment, the moltenextrudate may enter at 13. The operational direction may vary dependingon the requirements of the user.

The water that cools the plastic extrudate may enter tank trough 12through tooling 14. The water supply is stored in reservoir 18. Some ofthis water supply will be used generically to simply provide additionalcooling capability in auxiliary tank 11 and or in coordination withspray tubes (not shown) that may be outfitted.

Water from reservoir 18 also may enter the trough 12 through a varietyof inlet/outlet apertures which may be used as water inlets or outlets,discussed later: 51, 52, 53, 54, 55, 56, 64, 65, 66, 72, 73, 74. Thewater may enter these openings though line 120 in FIG. 4. Water ispushed through line 120 by water pump 19 for water control purposeseither inlet or outlet depending on desired setup. The water flow inthis line may be controlled electronically with potentiometer 23, FIG. 1and/or with valves 80 and 81, FIG. 4.

Water flow through pump 19 is specific to assist in developing desirablewater flow control in trough 12. Water pump 19 may be of severalspecific types including but not limited to rotary style, centrifugalstyle, AC electric, DC electric, positive displacement, metering pumpsetc.

Line 122, FIG. 4 provides water to auxiliary water tank 11, FIG. 1 andspray tubes from manifold 110 FIG. 4. Pump 21 recirculation pump, FIG. 1supplies water through heat exchanger 22, FIG. 1 and pumps water intomanifold 110, FIG. 4. Valve 94, FIG. 4 is the control of the main watersource for reservoir 18, FIG. 1.

Water may also be removed from tank trough 12 through a combination ofinlet/outlet apertures which may be used as outlets: 51, 52, 53, 54, 55,56, 64, 65, 66, 72, 73, 74. The flow may be controlled with valves 80,81, 82, and 83. The flow may also be controlled by pump 19 as an outletpump. Various combinations exist to add or remove water from previouslymentioned openings. Water flows through valves 82 and 83 into drip pan(not shown).

FIG. 3 further shows flow channels 57-63, 67, 68, 72-74. The flowchannels allow varying flow through the inlet/outlet apertures, and maydirect, control and stabilize flow of water. In one embodiment, the flowchannels may create different flow zones. For example, water may enterat aperture 53 and be directed by flow channel 60 along the outer edgeof the trough under a particular set of flow conditions. Because of thegeometry of the tank, the majority of the water from aperture 53 willpass into flow channel 59, and exit through aperture 54. This allows thezone along the outer edge of the trough to have a different flow profilecompared to other zones of the trough.

In a further embodiment, water may enter at aperture 52, be directed byflow channel 61, and the majority of that flow will pass into flowchannel 58, and may exit through aperture 55. It should be understoodthat further embodiments involve similar inlet and outlet flow tocorresponding flow channels. These further embodiments allow numerousflow zones to be created, and allow the zones to interact, therebycreating ideal conditions for the processing of the extrudate. Onenon-limiting example of interaction between the flow zones comprises afirst flow zone and a second flow zone adjacent to one another. Thefirst flow zone may have a first temperature at inlet, the second flowzone may have a different second temperature at inlet. At anintersection of zones there may be a heat exchange caused by conduction,convection and/or radiation. This heat exchange may result in the firstflow zone having a third temperature at outlet, and the second flow zonehaving a fourth temperature at outlet.

Potentiometer 23 controls the speed of pump 19 which is dedicated to thespecific water flow in or out of apertures 51, 52, 53, 54, 55, 56, 64,65, 66, 72, 73 or 74. Potentiometer 24 controls the speed to vacuumsystem 20 for vacuum level control.

During operation, water height in tank 12 may be optionally limited bystandpipe 87 and additionally controlled by previously mentioned pumps19 if so desired. Excess water may pass through standpipe 87 and intodrip pan (not shown) via line 124. Standpipe 88 is to control waterheight in water bath 16. Water will enter standpipe 88 and enter line125 which drains into drip pan (not shown).

Pump 21 forces circulation of water through heat exchanger 22 and intomanifold 110 via line 127. Manifold 110 may be used to supply water tolines 121 and 122 which is connected to sprayer/misters 89 in bath 16.Water may also be supplied to tooling 14 through line 121 and controlledwith valve 84. Additionally, a main water source may be supplied toreservoir 18 via opening 94. Should the water level in reservoir 18 falltoo low, float 95 will lower and open valve 94 and water will flow inuntil reaching desired level. Reservoir 18 is divided into two sectionssuch that 101 is open to the atmosphere and 100 is substantially closedto the atmosphere. Float 96 will lower when water level in 100 becomestoo low allowing water from 101 to flow in through opening 97 andthrough one way check valve 98. All water entering drip pan (not shown)is returned to reservoir 18, opening 101 via line 126.

Vacuum is applied to tank 12 via vacuum system 20. Vacuum may be appliedseparate of water as a dry vacuum or as a wet vacuum in combination ofboth air and water. Vacuum is applied via line 123 from reservoir 100through standpipe 86. Vacuum may be controlled electronically withpotentiometer 24 and valve 78. Lids 47 and 48 close on vacuum tank 12and water bath 16 to allow for closed atmosphere conditions. Brackets 46may support the water bath 16 vessel as well as lid 47 Vacuum inreservoir 100 appears in tank 12. Standpipe 87 in tank 12 is to controlwater level. Standpipe 86 is taller such that no water can flow inwardsand is for vacuum being applied via line 123. No water will pass intovacuum line 123.

Heat exchanger 22 has an inlet of chilled water through line 129 and theoutlet of tepid water through line 128.

Pressure transducer 143 and temperature transducer 144 within tank 12provide voltage along leads 142. The voltage appears in circuit diagramin FIG. 4 as a temperature and pressure reading. Pressure andtemperature displays appear on displays 35 and 34 respectively. Thepressure and temperature displays 35 and 34 may be particularly usefulfor applications of extruded tubing in industries having high levels ofregulation. For example a medical industry may have processingrequirements for tubing. The displays 35, 34 may allow for recording andmonitoring of the extrudate to ensure proper processing requirements.Flow rate sensors 90 and 91 are mounted in line with line 120 whichprovides voltage to displays such as at 33 to describe flow rate foradjustment references regarding water input to plurality of locations:51, 52, 53, 54, 55, 56, 64, 65, 66, 69, 70, 71 72, 73, or 74. Flow ratesensors 92 and 93 are mounted to measure flow rate for outlet of waterthrough plurality of locations: 51, 52, 53, 54, 55, 56, 64, 65, 66, 69,70, 71 72, 73, or 74, which may enter drip pan (not shown). Voltage fromsensors 92 and 93 is displayed on display 27 and 28. Voltage fromsensors 90, 91, 92, and 93 is further used as a reference such thatbalanced flow within tank 12 may be achieved and controlled.

The present invention preferably may include a control system that is incommunication with the temperature, pressure and flow readings notedabove. The control system operates by adjusting temperature, vacuum andwater flow based on these readings by adjusting various valves, vacuumpump speed, water pump speed, inlet and outlet water flow rate and inletand outlet water flow location, among other variables.

The vacuum sizing tank moves on wheels 36. Final adjustment is completedwith leveling screws 37. Exact positioning of vacuum tank system 11 isachieved with wheel 44, which moves system 11 fore and aft on linearbearing assembly 40 and 41. Wheel 45 moves system 11 upstream and downstream on linear bearing assembly 42 and 43. Wheel 49 moves system 11 upand down.

Preferably, all electrical components are housed in, or terminated in,electrical enclosures 38 or 39.

As is noted previously, the embodiment shown in these figures couldsimilarly be configured as an insert for an existing rectangular vacuumsizing tank, allowing retrofitting of existing tanks.

Turning now to FIG. 5, a cut away view of another embodiment of thepresent invention is provided. A vacuum sizing tank 531 is shaped as acylindrical pipe. Attached to an inlet side of the pipe is a flowcontroller 561. The flow controller 561 is cone shaped to direct inletfluid from inlet ports 551 in a smooth and uniform flow. It should beunderstood that inlet ports 551 may be positioned at various pointsalong the edge of the flow controller 561 and also on the surface of thecone of the flow controller 561. Fluid entering the tank 531 from theinlet ports 551 continues down the pipe, as well as travelling in pathsalong the conical surface of the flow controller 561. At a tip of theflow controller 561 is an opening 541 through which molten extrudateenters the tank 531. The flow controller 561 is attached to a base 521which forms the inlet ports 551 and attaches the flow controller 561 tothe tank 531. An adapter 511 is attached to the base 521. The adapter511 provides an attachment for fluid inlet tubing at apertures 571.

FIG. 6 provides a rear view of an embodiment of the present invention.The adapter 511 having inlet ports 571 is attached to the base 521 andforms a ring with a central aperture. An inner surface 611 of the flowcontroller can be seen. The inner surface 611 is also conically shaped.The base 521 is in turn attached to the tank 531 shown in a cutawayview.

FIG. 7 provides a partially exploded view of an embodiment of thepresent invention. The flow controller 561 is attached to the base 521,which in turn is attached to the tank 531. The adapter 511 is shownremoved from the base 521 showing an interior of the inlet ports 551. Aninterior 611 of the flow controller 561 is shown. In operation, theadapter 511 forms a reservoir into which the fluid flows through theinlet port 571. Fluid in the reservoir flows through the inlet ports 551and into the tank 531. Through precise control of the inlet fluid flowthrough the inlet ports 551 a fluid flow may be controlled to provideuniform, smooth flow with minimal eddying.

FIG. 8 provides a detail view of one embodiment of the trough of thepresent invention. A splitter 803 is positioned at an outlet end of thetrough. The splitter is constructed to divert fluid flow away from thecenter of the trough and towards a slit-shaped outlet 801 on each outeredge of the trough. An aperture 802 is sized and positioned to receivean extrudate exiting the trough.

FIG. 9 provides a perspective view of an embodiment of the trough. Asplitter 803 is positioned at an outlet end of the trough. The splitteris constructed to divert fluid flow away from the center of the troughand towards slit shaped outlets 801 on each outer edge of the trough. Anaperture 802 is sized and positioned to receive an extrudate exiting thetrough. Outlet tooling 905 is attached in fluid communication with theoutlets 801. The outlet tooling 905 is configured with a plurality ofapertures to optimize outlet flow. In one embodiment, the outlet tooling905 may be configured to nearly eliminate eddies and dead spots near theoutlets 801 within the tank. The tank trough has a curved portion 901along its length. A bottom of the trough 902 is flat to slightly curved.Inlet flow tooling 903 is formed, in this embodiment, as a plurality ofsmall apertures arranged in a shape substantially matching a crosssection of the trough. The tooling 903 further forms a central aperture904 through which fluid and/or extrudate may enter the trough. Thecentral aperture 904 may be sized and configured to allow attachment ofadditional tooling to accommodate extrudate, additional fluid inlet, andthe like.

As is noted previously, the embodiment shown in these figures couldsimilarly be configured as an insert for an existing rectangular vacuumsizing tank, allowing retrofitting of existing tanks.

While several embodiments of the present invention have been describedand illustrated herein, those of ordinary skill in the art will readilyenvision a variety of other means and/or structures for performing thefunctions and/or obtaining one or more of the advantages describedherein, and each of such variations and/or modifications is deemed to bewithin the scope of the present invention. More generally, those skilledin the art will readily appreciate that all parameters, dimensions,materials, and configurations will depend upon the specific applicationor applications for which the teachings of the present invention is/areused. Those skilled in the art will recognize, or be able to ascertainusing no more than routine experimentation, many equivalents to thespecific embodiments of the invention described herein. It is therefore,to be understood that the foregoing embodiments are presented by way ofexample only and that, within the scope of the appended claims andequivalents thereto; the invention may be practiced otherwise than asspecifically described and claimed. The present invention is directed toeach individual feature, system, article, material, kit and/or methoddescribed herein. In addition, any combination of two or more suchfeatures, systems, articles, materials, kits, and/or methods are notmutually inconsistent, are included within the scope of the presentinvention.

What is claimed is:
 1. A sizing tank comprising: a trough capable ofholding a liquid, the trough having a first opening for an ingress of aplastic extrudate and a second opening for egress of the plasticextrudate; a pump system comprising a pump, the pump system constructedand arranged to provide a fluid flow within the trough and control fluidflow within the trough, a plurality of fluid inlets connected to thepump allowing fluid to enter the trough in a plurality of differentpositions; a plurality of fluid outlets allowing fluid to exit from thetrough in a plurality of different positions; and wherein the pluralityof fluid inlets and plurality of fluid outlets are constructed andarranged to provide a fluid flow within the trough, and configured toform a flow zone within the trough, the flow zone having a controlledand uniform flow profile.
 2. The sizing tank of claim 1 wherein thepump, the plurality of fluid inlets and plurality of fluid outlets arecapable of controlling a fluid flow within the trough by forming aplurality of flow zones, the plurality of flow zones having asubstantially controlled and substantially uniform flow profilethroughout each zone.
 3. The sizing tank of claim 1 wherein the flowprofile of the flow zone is substantially laminar.
 4. The sizing tank ofclaim 1 wherein the flow profile of the flow zone is controlled toprevent formation of an eddy at or near a surface of the plasticextrudate.
 5. The sizing tank of claim 1 wherein the trough furthercomprises a plurality of flow channels, the plurality of flow channelsbeing formed by the tank, a first of the plurality of fluid inlets beingpositioned at one end of a first of the plurality of flow channels, anopposite end of the flow channel opening into the trough and directingat least a portion of the fluid flow from the first of the plurality offluid inlets.
 6. The sizing tank of claim 1 wherein one of the pluralityof fluid inlets having a corresponding one of the plurality of fluidoutlets, such that substantially all fluid entering the trough from theone of the plurality of fluid inlets exits the trough from thecorresponding one of the plurality of fluid outlets.
 7. The sizing tankof claim 2 wherein the plurality of flow zones are defined along a widthof the tank, with flow of each of the plurality of flow zones beingsubstantially parallel to a direction of the plastic extrudate, aninterface of adjacent flow zones causing an interaction ofcharacteristics between the adjacent flow zones.
 8. The sizing tank ofclaim 7 further comprising a first of the plurality of zones adjacent toa second of the plurality of zones, a fluid of the first of theplurality of zones having a first temperature at inlet to the tank, afluid of the second of the plurality of zones having a secondtemperature different from the first temperature at inlet to the tank;wherein an interaction of characteristics between the adjacent flowzones causes the fluid of the first of the plurality of zones to reach athird temperature at outlet from the tank, and causes the fluid of thesecond of the plurality of zones to reach a fourth temperature at outletfrom the tank.
 9. The sizing tank of claim 1 further comprising a flowsplitter positioned on an outlet end of the trough, the flow splitterhaving a substantially ‘v’ shape, a pointed end of the flow splitterbeing positioned at a center of a width of the trough, facing a fluidflow in the trough, the flow splitter constructed and arranged to directfluid flow towards an outer edge of the trough, one of the plurality offluid outlets being positioned at a corner formed by a broad end of theflow splitter.
 10. The sizing tank of claim 1 further comprising asecond pump, the pump being attached to at least one of the plurality offluid inlets, the second pump being attached to at least one of theplurality of fluid outlets.
 11. The sizing tank of claim 1 furthercomprising a fluid control system, the fluid control system comprising:a flow sensor disposed within the trough, configured to monitor thefluid flow within the tank; and a fluid controller in communication withthe flow sensor, the controller configured to adjust the pump toincrease the fluid flow when the flow sensor senses a decrease in flow,and configured to adjust the pump to decrease the fluid flow when theflow sensor senses an increase in flow, the fluid controller being incommunication with the pump.
 12. The sizing tank of claim 11 furthercomprising a programmable interface allowing programming of a pluralityof different fluid flow controls into the fluid controller.
 13. Thesizing tank of claim 1 further comprising: a pressure gauge disposed onan exterior of the tank providing a display of a pressure within thetrough; a temperature gauge disposed on an exterior of the tankproviding a display of a fluid temperature at a position within thetrough; a flow gauge disposed on an exterior of the tank providing adisplay of a fluid flow rate at a position within the trough.
 14. Asizing tank comprising: a cylindrical trough formed by the tank capableof holding a liquid, the tank having a first end for ingress of aplastic extrudate and a second end for egress of the plastic extrudate,the extrudate being cylindrically shaped at ingress; a pump constructedand arranged to provide a fluid flow to the tank; a conically shapedflow controller positioned at the first end, the flow controller formingan opening at a tip end for the ingress of the plastic extrudate; aplurality of fluid inlet ports formed about a circumference of a base ofthe conically shaped flow controller, the plurality of fluid inlet portsbeing connected to the pump and constructed and arranged to direct afluid flow into the tank; a plurality of fluid outlet ports allowingfluid to exit from the tank; and wherein the conically shaped flowcontroller, the plurality of fluid inlet ports, and the plurality offluid outlet ports are formed to direct a fluid flow in a uniform andcontrolled flow profile throughout the cylindrical tank and about thecylindrically shaped extrudate.
 15. The sizing tank of claim 14 furthercomprising a control system, the control system comprising: a sensorconfigured to sense an operating parameter within the tank; acomputerized controller in communication with the sensor and configuredto control the operating parameter sensed, the controller configured tocontrol the operating parameter sensed when the sensor senses that theoperating parameter is outside of a specified tolerance.
 16. A systemfor retrofitting a rectangular sizing tank comprising: an insert havingan exterior sized to fit within the rectangular sizing tank, and aninterior defining a trough capable of holding a liquid, the troughhaving a first opening for an ingress of a plastic extrudate and asecond opening for egress of the plastic extrudate aligning withopenings of the rectangular sizing tank; a pump system comprising apump, the pump system constructed and arranged to provide a fluid flowwithin the trough and control fluid flow within the trough, a pluralityof fluid inlets defined by the insert connected to the pump and allowingfluid to enter the trough in a plurality of different positions; aplurality of fluid outlets defined by the insert allowing fluid to exitfrom the trough in a plurality of different positions; and wherein theplurality of fluid inlets and plurality of fluid outlets are constructedand arranged to provide a fluid flow within the trough, and configuredto form a flow zone within the trough, the flow zone having a controlledand uniform flow profile.
 17. The system of claim 16 wherein the flowprofile of the flow zone is substantially laminar.
 18. The system ofclaim 16 wherein the pump, the plurality of fluid inlets and pluralityof fluid outlets are capable of controlling a fluid flow within thetrough by forming a plurality of flow zones, the plurality of flow zoneshaving a substantially controlled and substantially uniform flow profilethroughout each zone.
 19. The system of claim 16 further comprising: apressure gauge disposed on an exterior of the tank providing a displayof a pressure within the trough; a temperature gauge disposed on anexterior of the tank providing a display of a fluid temperature at aposition within the trough; a flow gauge disposed on an exterior of thetank providing a display of a fluid flow rate at a position within thetrough.
 20. The system of claim 19 wherein the trough further comprisesa plurality of flow channels, the plurality of flow channels beingformed by the tank, a first of the plurality of fluid inlets beingpositioned at one end of a first of the plurality of flow channels, anopposite end of the flow channel opening into the trough and directingat least a portion of the fluid flow from the first of the plurality offluid inlets.